The present invention relates to a tool handle, and, more particularly, to a tool handle for receiving a blade member in a manner permitting continuous maintenance of overall tool length irrespective of blade wear.
Engraving tools are well known in the art, and consist generally of a spike-shaped blade member which extends from a handle suitably configured for reception in the palm of the hand. Tools of this type are used for a variety of purposes in addition to engraving. For example, engraving tools are use by stone setters to mount diamonds and other stones in a setting. The process is carried out by fitting the stone in a receiving hole formed in the metal support to which the stone is to be mountably secured, and compressing the metal at points along a periphery of the receiving hole to form a series of beads protruding inwardly above, and in contact peripherally with, the stone, thus captively holding the stone in the setting. To maintain precise control while performing this operation, the tool is held in the hand with the handle supported at its base on the heel of the palm, and with the blade supported proximate a terminal end thereof by a suitable extended finger of the same hand in supportive contact therewith.
Repeated use of the engraving tool in performance of such tasks results in blade wear, requiring regrinding and a resultant shortening of the blade. This blade shortening adversely affects proper handling of the tool, since the distance that the blade extends forward of the handle is preferably of a constant length selected for ideal comfort and control, predetermined based upon the characteristics of the individual user's hand.
To address this need, a variety of handles are currently available, each permitting the base of a blade to be inserted to different preset depth. Selection of a suitable handle thereby allows incremental control over the overall length of the tool when a blade is inserted therein. In this manner, as a blade is worn, and its length is diminished, a handle permitting a shallower degree of blade insertion is selected to compensate for the decrease in blade length. Although somewhat effective, such solution requires purchase and storage of a plurality of handles, and does not permit continuous blade reception depth adjustment.
A tool handle permitting simple and reliable adjustment of an overall tool length when a blade is received therein, and which advantageously permits continuous adjustment of a permitted degree of blade insertion into the handle, would therefore be highly desirable.
Accordingly, it is an object of the invention to provide a tool handle which overcomes the drawbacks of the prior art.
It is a further object of the invention to provide a tool handle which permits a user thereof to selectively control a permitted depth of insertion of a blade received therein such that the degree of extension of the blade can be adjusted as needed, for example, to maintain constant tool length irrespective of blade wear.